Toxicological evaluation for biomaterials: Examinations of radiation vulcanized natural rubber latex

Abstract

Our studies indicated that the thickness of the inflammatory layer was the most useful parameter to evaluate tissue response among 13 histological parameters. There was good correlation between the cytotoxicity and the thickness of inflammatory layer. Histological findings showed that the inflammatory layer of radiation vulcanized natural rubber latex (RVNRL) films involved a slightly higher response than the negative implant at the 3rd post operative day although the inflammatory layer showed almost the same degree as the negative controls at the 7th day. The cytotoxic potential of the extracts prepared from RVNRL films was found to be weak by the colony assay. The hemolytic activity was also detected in the extracts of RVNRL films. The lysis of red blood cells and the release of haemoglobin was clearly caused by RVNRL film. Though the cytotoxic and tissue irritative activities of RVNRL are considered much weaker then sulfur-vulcanized latices, it was suggested that RVNRL contains some unknown substances showing weak toxicities including hemolysis.